title: Risk factors for intrauterine constraint are associated with ultrasonographically detected severe fibrosis in early congenital muscular torticollis.
abstract: OBJECTIVE
  The etiology of congenital muscular torticollis (CMT) remains controversial. Ultrasonographically, severe fibrosis involving the entire sternocleidomastoid muscle (SCM; type 3 or 4) fibrosis has been associated with poor clinical outcomes and indicates a chronic state of the condition. The purpose of this study was to test whether or not type 3 or 4 fibrosis detected early after birth is associated with factors related to prolonged intrauterine constraint.
  
  
  METHODS
  Sixty-seven patients (age, <3 months) with CMT were classified into 4 different ultrasonographic types according to the severity of SCM fibrosis. The odds ratio for the relationship between probability of type 3 or 4 and factors related to intrauterine constraint were calculated by a multivariate logistic regression model.
  
  
  RESULTS
  None were classified as type 4. Twenty-three patients (34%) had a history of breech presentation, and 21 (91.3%) of them were delivered by elective cesarean section without likelihood of birth trauma. Compared with normal pregnancy, breech presentation and oligohydramnios showed a 6.7 or 7.5 times higher probability for type 3 fibrosis, respectively.
  
  
  CONCLUSIONS
  Risk factors for intrauterine constraint appear to be associated with ultrasonographically detected severe fibrosis involving the entire SCM muscle in early presenting CMT.
authors.affiliation: Department of Rehabilitation Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University, School of Medicine, Seoul, South Korea.
authors.forename: Yong-Taek
authors.initials: YT
authors.lastname: Lee
authors.forename: Soo Kyoung
authors.initials: SK
authors.lastname: Cho
authors.forename: Kyungjae
authors.initials: K
authors.lastname: Yoon
authors.forename: Hun Kyu
authors.initials: HK
authors.lastname: Shin
authors.forename: Eugene
authors.initials: E
authors.lastname: Kim
authors.forename: Yong-Bum
authors.initials: YB
authors.lastname: Kim
authors.forename: Won-Serk
authors.initials: WS
authors.lastname: Kim
authors.forename: Jung Mi
authors.initials: JM
authors.lastname: Chun
authors.forename: Byung Hee
authors.initials: BH
authors.lastname: Han
mesh_terms: D001720:Birth Injuries; D001946:Breech Presentation / Q000453:epidemiology; D002585:Cesarean Section / Q000706:statistics & numerical data; D005260:Female; D005324:Fetal Movement; D005355:Fibrosis; D006801:Humans; D007103:Immobilization / Q000009:adverse effects*; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008954:Models, Biological; D019838:Neck Injuries; D009334:Neck Muscles / Q000000981:diagnostic imaging / Q000196:embryology / Q000473:pathology*; D016104:Oligohydramnios / Q000453:epidemiology; D011247:Pregnancy; D012307:Risk Factors; D014103:Torticollis / Q000151:congenital / Q000000981:diagnostic imaging / Q000196:embryology / Q000209:etiology; D014463:Ultrasonography